May 26 (UPI) -- President Donald Trump has criticized President Vladimir Putin of Russia after the Kremlin launched hundreds of missiles and drones at its neighbor over the weekend.

Trump told reporters in New Jersey before boarding Air Force One that he was "not happy" with Putin over the recent attacks.

"He's killing a lot of people, and I don't know what the hell happened to Putin; I've known him a long time. Always gotten along with him, but he's sending rockets into cities and killing people, and I don't like it at all," Trump said.

At least a dozen people were killed in Ukraine, officials said, after Russia launched 367 rockets and drones at Ukrainian cities on Saturday, marking one of the largest such attacks amid the three-year-old war.

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